The purpose of this study is to extend and rigorously test a promising school-based program for preventing multiple risk behaviors as youth move into their high school years. Coping And Support Training (CAST) is a 12-session, small group prevention program that incorporates a parent component with a subsequent family booster session. The program addresses risk factors associated with adolescent anger/aggression, depression, substance use and school failure by building health-promoting competency skills (problem solving/decision-making, emotion regulation) and social support resources (pro-social peers, family, and school support). This proposal responds to NIH's call: Enhancing Adolescent Health Promotion across Multiple High Risk Behaviors (PA-02-159). Participants will include 320 at-risk 13-to 14 year-old 8th graders from large, public middle schools in 3 school districts. Youth will be randomly assigned (n=160) to one of two conditions (CAST or "school as usual"). Youth in the prevention program compared to the control group are expected to show reduced problem behaviors (anger control problems, aggression, depression); and, at the longer-term follow-up, reduced suicide risk, risky sexual behaviors, ATOD use, and increased school performance. Youth will be assessed 6 times from 8th to 10th grade. Tests will be conducted on short- and longer-term efficacy effects and the potential moderating effects of gender, ethnicity, and risk-level on outcomes. Process evaluation will be used to ensure implementation fidelity, and to monitor and stem negative peer influence. Tests will be conducted on models derived from a theoretically-specified model, positing that CAST reduces co-occurring health risk behaviors through the mediating effects of enhanced personal competencies and pro-social network building, which in turn attenuate the negative effects of antecedent risk factors. This study should provide evidence of program efficacy and begin to explicate mechanisms by which skills-training and social support reduce multiple risk behaviors while enhancing health-promoting behaviors.